Megan's 5 cttw Cushion Cut Cubic Zirconia Stud Earrings These elegant prong set, cushion cut diamond cubic zirconia stud earrings are classically beautiful. Each earring measures approximately 2.5 carats (8mm). They are set in sterling silver and rhodium electroplated for the stylish gleam of platinum and feature post backings. They are similar to cushion cut diamond stud earrings celebrities and entertainers are known to wear casually and on the red carpet.